Between 1987 and 2003, the prevalence of autism has increased by 634% according to the California Department of Developmental Services. Many other studies and recent statistics also show an increase in prevalence rates. But what does this mean? As shown in this graph, the actual increase in cases of autism between 1992 and 2005 is much higher than what was predicted. This increase in cases has led a lot of people to think that there is an autism epidemic, citing a number of causes, including vaccines and parental neglect. But to put it simply, there is no such thing as an autism epidemic. So what can we attribute this rise to? The truth is we don’t really know what causes autism. Due to the lack of scientific evidence, many people create their own theories and from there, several misconceptions arise. A common misconception is that autism is caused by the Measles, Mumps, and Rubella, or MMR, vaccine. As shown in this bar graph, a growing number of people believe that vaccines play a role in autism, especially in younger age groups, those more likely to have children soon. However, multiple studies have found no connection between the two. A large study of over 1000 cases failed to find any positive relationships between MMR immunization and the diagnosis of autism. Studies that do show some sort of association between vaccines and the rates of autism are often limited and misleading because they look at a relatively small amount of people Even if results were accurate, they can’t be applied to the general population because different countries have different vaccination practices. Every country provides and requires different vaccines, but autism seems to be rising everywhere regardless. One of the more long standing theories surrounding the cause of autism has been that of the “refrigerator mother,” an idea that originated around 1950 that blames autism on parents for being cold and reserved, causing their kids to reclude and not want to associate with anyone. This has long been discarded as a valid theory. A more recent theory is that the older parents are when they have a child, the more likely the child will have autism. But older parents are also more likely to have children with developmental disorders other than autism, such as down syndrome, so this cannot be a direct cause of autism. There are likely to be environmental, genetic, and other unknown factors that are responsible for autism, but the search for a cause is messy and ongoing. People have cited correlations between storm exposure during pregnancy, chemicals in food and pesticides, as well as some genes that seem to play a role. The truth is that while some of these may play a factor, none are truly the cause of autism. Scientists have examined what could explain the rise in prevalence rates, if not these misconceptions; one common contributor to the increase is the change in diagnostic criteria. In the newest version of the Diagnostic and Statistical Manual, several other disorders were made a part of the Autism Spectrum Disorder diagnosis. Children and adults previously diagnosed with Asperger’s, for example, are now diagnosed as having autism. This change means the number of cases would go up without increasing the number of people diagnosed with developmental disorders. A 2010 study looked at the amount of cases reported for several developmental disorders and showed that while rates of autism has gone up, rates of these other disorders have gone down, implying that there are no new cases, just different diagnoses. Additionally, researchers have recently been trying to collect data from more people to gain a better appreciation for the true nature of autism, leading to more cases of autism being identified and studied. A 2010 study of elementary schools in Wisconsin gives us a clear example of this. As schools began to adopt more recent criteria for identifying cases of autism, the number of reported cases increased drastically. Schools that adopted these criteria at a later time tended to report a larger increase, which is consistent with the idea that newer diagnostic criteria play a large role in the rising prevalence we’re seeing today. This phenomenon is gradually attracting more public attention among school professionals and laypeople alike. It turns out that this might actually be a contributing factor as well. An explanation is that children living in close proximity with children previously diagnosed with autism are more likely to have autism, because of social influence theory. The Social Influence Theory is the increased awareness of autism when parents socialize or/interact with one another at places like schools, playgrounds, shops etc. This leads to the exchange of information about their own child’s development. So if there isn’t an epidemic, why does the increase in ASD diagnoses matter? Although there is no true epidemic, the rates of people being diagnosed and treated for autism is more than previously thought; autism is no longer a rare disease affecting only a few children. Because of the rising prevalence rates of autism, the way we approach disabilities has to change. society will need to create a more inclusive environment and provide more options for those with autism. Another important factor is that if the rate of autism diagnoses continues increases at current rates, the amount of funding provided by public policy will not be adequate to meet rising needs. Additional research will equip politicians with data to support greater budget allocation to ASD patients. They will have better insight into the type and volume of treatment options and educational resources that need to be available. Lastly, it is important to note the dangers of being misinformed. Believing that there is an autism epidemic caused by vaccines can bring about a true epidemic of potentially deadly diseases. Don’t wait, vaccinate!